Calcification Lab

“With increasing degree of calcification, the concentration of NaOH increases. The relationship between the concentration of NaOH and the factors in the calcified red mud liquor is given by three Equations (16–18):
N_NaOH=1.29(N_1 m_1-N_2 (m_2-N_NaOH/1.29) (16) m2 = m1+m1N3 (17) r = 1000/m2 (18) where NNaOH is the concentration of NaOH in the liquor after calcification (g/L) , N1, N2, and N3 are the mass composition of Na2O in dry red mud befor/after calcification and the addition of CaO (%), m1 is the mass of fresh red mud added to …show more content…
The activity coefficient was found to be in the range 0.683–0.731 as reported by Lide et al.,[29] whereas the maximum activity is found in the range 0.146–0.396. Normally, the contribution of NaOH activity to 〖∆G〗_T ranges from −4.59 kJ to −20.67 kJ.”
Comment 6: Adding water to dry red mud, the red mud slurry was made. More properties of red mud slurry will be needed including water content.
Response: Fig. 5a was upgraded with the distributions of powder size of red mud measured in the three cases. The diagram of viscosity of red mud slurry vs. liquid–solid ratio and viscosities of red mud slurry with additive of CaO is added in the revised manuscript as shown in Fig. 6 to represent the rheological property of red mud slurry. Discussion has been added in the revised manuscript (page 15, line 271 to page 16, line 296) to clarify the properties of red mud